1. Field of the Invention
The present invention relates generally to dies for extruding materials, and more specifically to die adjustment devices for adjusting a gap or gaps between adjacent portions of die bodies.
2. Background Information
Flat sheet or film extrusion dies typically include a pair of die bodies that operate to form an outlet through which material is extruded. Each die body may typically include a lip, where the lips may at least partially form the outlet. Further, at least one of the lips may be a flexible lip that is capable of being adjusted to provide a particular sheet or film thickness of the material.
The flexible lips of the prior art extrusion dies may be adjusted and controlled by a controlling mechanism, as exemplarily described in U.S. Pat. No. 6,663,375 (“'375”) to Ulcej and U.S. Pat. No. 6,017,207 (“207”) to Druschel. As shown in the '375 and '207 patents, a controlling mechanism may include links (or push/pull blocks in the case of the '207 patent), where the links (or blocks) directly push or pull on a portion of a flexible lip to cause movement of the flexible lip. Further, the links (or blocks) may be actuated by movement of an adjustment bar that slides along a main portion of the die body having the flexible lip.
While the prior art has provided examples of features of die lip adjusting mechanisms, there is always room for further improvement.